I just changed rims on both rears and went from stock 7.5 inches width to 8 inches. I used my old Yokohama AD07s on the new rims, since they have a fair amount of tread left. I got the wheels back from the tire store today where I had them mounted and they don't seem to hold pressure very well. They look fine and don't have any obvious holes or gashes. Is this normal? Do I just have to give them time to conform to the different width, even if it is only half an inch?